1. Field of the Invention
The present invention relates to processes and microorganisms for producing L-ornithine by fermentation.
2. Discussion of the Background
L-Ornithine is an important component of drugs for stimulating liver functions, total amino acid preparations, etc.
Some microorganisms belonging to the genus Brevibacterium or to the genus Corynebacterium are known to produce L-ornithine. These include citrulline or arginine auxotroph which belong to the genus Brevibacterium (Japanese Patent Publication No. 43-8712), citrulline or arginine auxotroph which belong to the genus Bacillus (Japanese Patent Publication No. 43-10996), citrulline or arginine analogues which belong to the genus Arthrobacter (Japanese Patent Publication No. 44-24303), variants having resistance to arginine analogues belonging to the genus Corynebacterium (Japanese Patent Application Laid-Open No. 53-24096), or variants which belong to the genus Corynebacterium having resistance to 2-thiazolealanine, sulfaguanidine or 2-fluoropyruvic acid (Japanese Patent Application Laid-Open No. 61-119194)
To reduce the costs of producing L-ornithine however, in particular industrial-scale production costs, there is a current need for bacterial strains providing improved fermentation yields of this material.